NGC 6820 and CAB2008-V39 (Vulpecula) N E
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Filter Performance Comparisons for Some Common Nebulae
Filter Performance Comparisons For Some Common Nebulae By Dave Knisely Light Pollution and various “nebula” filters have been around since the late 1970’s, and amateurs have been using them ever since to bring out detail (and even some objects) which were difficult to impossible to see before in modest apertures. When I started using them in the early 1980’s, specific information about which filter might work on a given object (or even whether certain filters were useful at all) was often hard to come by. Even those accounts that were available often had incomplete or inaccurate information. Getting some observational experience with the Lumicon line of filters helped, but there were still some unanswered questions. I wondered how the various filters would rank on- average against each other for a large number of objects, and whether there was a “best overall” filter. In particular, I also wondered if the much-maligned H-Beta filter was useful on more objects than the two or three targets most often mentioned in publications. In the summer of 1999, I decided to begin some more comprehensive observations to try and answer these questions and determine how to best use these filters overall. I formulated a basic survey covering a moderate number of emission and planetary nebulae to obtain some statistics on filter performance to try to address the following questions: 1. How do the various filter types compare as to what (on average) they show on a given nebula? 2. Is there one overall “best” nebula filter which will work on the largest number of objects? 3. -
Winter Constellations
Winter Constellations *Orion *Canis Major *Monoceros *Canis Minor *Gemini *Auriga *Taurus *Eradinus *Lepus *Monoceros *Cancer *Lynx *Ursa Major *Ursa Minor *Draco *Camelopardalis *Cassiopeia *Cepheus *Andromeda *Perseus *Lacerta *Pegasus *Triangulum *Aries *Pisces *Cetus *Leo (rising) *Hydra (rising) *Canes Venatici (rising) Orion--Myth: Orion, the great hunter. In one myth, Orion boasted he would kill all the wild animals on the earth. But, the earth goddess Gaia, who was the protector of all animals, produced a gigantic scorpion, whose body was so heavily encased that Orion was unable to pierce through the armour, and was himself stung to death. His companion Artemis was greatly saddened and arranged for Orion to be immortalised among the stars. Scorpius, the scorpion, was placed on the opposite side of the sky so that Orion would never be hurt by it again. To this day, Orion is never seen in the sky at the same time as Scorpius. DSO’s ● ***M42 “Orion Nebula” (Neb) with Trapezium A stellar nursery where new stars are being born, perhaps a thousand stars. These are immense clouds of interstellar gas and dust collapse inward to form stars, mainly of ionized hydrogen which gives off the red glow so dominant, and also ionized greenish oxygen gas. The youngest stars may be less than 300,000 years old, even as young as 10,000 years old (compared to the Sun, 4.6 billion years old). 1300 ly. 1 ● *M43--(Neb) “De Marin’s Nebula” The star-forming “comma-shaped” region connected to the Orion Nebula. ● *M78--(Neb) Hard to see. A star-forming region connected to the Orion Nebula. -
A Basic Requirement for Studying the Heavens Is Determining Where In
Abasic requirement for studying the heavens is determining where in the sky things are. To specify sky positions, astronomers have developed several coordinate systems. Each uses a coordinate grid projected on to the celestial sphere, in analogy to the geographic coordinate system used on the surface of the Earth. The coordinate systems differ only in their choice of the fundamental plane, which divides the sky into two equal hemispheres along a great circle (the fundamental plane of the geographic system is the Earth's equator) . Each coordinate system is named for its choice of fundamental plane. The equatorial coordinate system is probably the most widely used celestial coordinate system. It is also the one most closely related to the geographic coordinate system, because they use the same fun damental plane and the same poles. The projection of the Earth's equator onto the celestial sphere is called the celestial equator. Similarly, projecting the geographic poles on to the celest ial sphere defines the north and south celestial poles. However, there is an important difference between the equatorial and geographic coordinate systems: the geographic system is fixed to the Earth; it rotates as the Earth does . The equatorial system is fixed to the stars, so it appears to rotate across the sky with the stars, but of course it's really the Earth rotating under the fixed sky. The latitudinal (latitude-like) angle of the equatorial system is called declination (Dec for short) . It measures the angle of an object above or below the celestial equator. The longitud inal angle is called the right ascension (RA for short). -
Astronomy 2008 Index
Astronomy Magazine Article Title Index 10 rising stars of astronomy, 8:60–8:63 1.5 million galaxies revealed, 3:41–3:43 185 million years before the dinosaurs’ demise, did an asteroid nearly end life on Earth?, 4:34–4:39 A Aligned aurorae, 8:27 All about the Veil Nebula, 6:56–6:61 Amateur astronomy’s greatest generation, 8:68–8:71 Amateurs see fireballs from U.S. satellite kill, 7:24 Another Earth, 6:13 Another super-Earth discovered, 9:21 Antares gang, The, 7:18 Antimatter traced, 5:23 Are big-planet systems uncommon?, 10:23 Are super-sized Earths the new frontier?, 11:26–11:31 Are these space rocks from Mercury?, 11:32–11:37 Are we done yet?, 4:14 Are we looking for life in the right places?, 7:28–7:33 Ask the aliens, 3:12 Asteroid sleuths find the dino killer, 1:20 Astro-humiliation, 10:14 Astroimaging over ancient Greece, 12:64–12:69 Astronaut rescue rocket revs up, 11:22 Astronomers spy a giant particle accelerator in the sky, 5:21 Astronomers unearth a star’s death secrets, 10:18 Astronomers witness alien star flip-out, 6:27 Astronomy magazine’s first 35 years, 8:supplement Astronomy’s guide to Go-to telescopes, 10:supplement Auroral storm trigger confirmed, 11:18 B Backstage at Astronomy, 8:76–8:82 Basking in the Sun, 5:16 Biggest planet’s 5 deepest mysteries, The, 1:38–1:43 Binary pulsar test affirms relativity, 10:21 Binocular Telescope snaps first image, 6:21 Black hole sets a record, 2:20 Black holes wind up galaxy arms, 9:19 Brightest starburst galaxy discovered, 12:23 C Calling all space probes, 10:64–10:65 Calling on Cassiopeia, 11:76 Canada to launch new asteroid hunter, 11:19 Canada’s handy robot, 1:24 Cannibal next door, The, 3:38 Capture images of our local star, 4:66–4:67 Cassini confirms Titan lakes, 12:27 Cassini scopes Saturn’s two-toned moon, 1:25 Cassini “tastes” Enceladus’ plumes, 7:26 Cepheus’ fall delights, 10:85 Choose the dome that’s right for you, 5:70–5:71 Clearing the air about seeing vs. -
Interstellar Extinction in the Direction of Young Open Star Clusters
ISSN (Online) 2393-8021 ISSN (Print) 2394-1588 IARJSET International Advanced Research Journal in Science, Engineering and Technology Vol. 6, Issue 5, May 2019 Interstellar Extinction in the Direction of Young Open Star Clusters Alok K. Durgapal* Center of Advanced Study, Department of Physics, D. S. B. Campus, Kumaun University Nainital, India Abstract: The total to selective extinction law in optical and near-IR wavelengths for twenty young open star clusters namely Berkeley 7, Collinder 69, Hogg 10, NGC 2362, Czernik 43, NGC 6530, NGC 6871, Bochum 10, Haffner 18, IC 4996, NGC 2384, NGC 6193, NGC 6618, NGC 7160, Collinder 232, Haffner 19, NGC 2401, NGC 6231, NGC 6823, NGC 7380 have been studied. It is found that fifteen clusters follow normal extinction law and five clusters show an anomalous behavior. Keywords: Star cluster: Reddening, interstellar dust- Interstellar extinction I. INTRODUCTION The interstellar dust which is remnant of star formation process can transmit and redirect the light of stars ([2]). As a result it becomes very difficult to determine accurate distances and magnitudes of astronomical objects ([11]); to overcome this difficulty we must have knowledge of composition of interstellar dust in every line of sight. The interstellar extinction is caused either by general interstellar medium (ISM) or by localized region of higher mean density ([9], [15]). Study of interstellar extinction provides information about components of the molecular cloud from which a star was formed. Young stars contain dust around them so young open star clusters are the ideal objects for extinction study ([5], [8], [10], [16], [17]). First started with Trumpler in 1920 and then many investigators studied extinction in the Galaxy. -
Übersicht NGC-Objektauswahl Cepheus Zur Übersichtskarte
NGC-Objektauswahl Cepheus NGC 40 NGC 7055 NGC 7354 NGC 188 NGC 7076 NGC 7380 NGC 1184 NGC 7129 NGC 7419 NGC 1544 NGC 7139 NGC 7423 NGC 2276 NGC 7142 NGC 7429 NGC 2300 NGC 7160 NGC 7510 NGC 6939 NGC 7226 NGC 7538 NGC 6949 NGC 7235 NGC 7708 NGC 6951 NGC 7261 NGC 7762 NGC 7023 NGC 7281 NGC 7822 Sternbild- Übersicht Zur Objektauswahl: Nummer anklicken Zur Übersichtskarte: Objekt anklicken Sternbildübersicht Auswahl NGC 40_7708 Aufsuchkarte Auswahl NGC 188_Aufsuchkarte 2 UMi 2 Auswahl NGC 1184 Aufsuchkarte Auswahl NGC 1544_2276_2300 Aufsuchkarte Auswahl NGC 6939 Aufsuchkarte Auswahl NGC 6949_6951 Aufsuchkarte Auswahl NGC 7023 Aufsuchkarte Auswahl NGC 7055 Aufsuchkarte Auswahl NGC 7076 Aufsuchkarte Auswahl NGC 7129_7142 Aufsuchkarte Auswahl NGC 7139_7160 Aufsuchkarte Auswahl NGC 7226_7235 Aufsuchkarte Auswahl N 7261_7281 Aufsuchkarte Auswahl NGC 7354_7419_7429_7510_7538 Aufsuchkarte Auswahl NGC 7380_7423 Aufsuchkarte Auswahl NGC 7762_7822 Aufsuchkarte Auswahl NGC 40 Übersichtskarte Aufsuch- Auswahl karte NGC 188 Übersichtskarte Aufsuch- Auswahl karte NGC 1184 Übersichtskarte Aufsuch- Auswahl karte NGC 1544 Übersichtskarte Aufsuch- Auswahl karte N 2276_N 2300 Übersichtskarte Aufsuch- Auswahl karte NGC 6939 Übersichtskarte Aufsuch- Auswahl karte NGC 6949 Übersichtskarte Aufsuch- Auswahl karte NGC 6951 Übersichtskarte Aufsuch- Auswahl karte NGC 7023 Übersichtskarte Aufsuch- Auswahl karte NGC 7055 Übersichtskarte Aufsuch- Auswahl karte NGC 7076 Übersichtskarte Aufsuch- Auswahl karte NGC 7129_7142 Übersichtskarte Aufsuch- Auswahl karte NGC 7139 -
Wide-Field Plate Archive of the University Observatory Jena
Astron. Nachr. / AN 999, No.88, 789–794 (2014) / DOI please set DOI! Wide-Field Plate Archive of the University Observatory Jena ⋆ A.V. Poghosyan1, W. Pfau1, K.P. Tsvetkova2, M. Mugrauer1, M.K. Tsvetkov2,3, V.V. Hambaryan1,⋆⋆, R. Neuhauser¨ 1, and D.G.Kalaglarsky2 1 Astrophysikalisches Institut und Universit¨ats-Sternwarte Jena, Schillerg¨aß chen 2, D-07745 Jena, Germany 2 Institute of Mathematics and Informatics, Bulgarian Academy of Sciences, Sofia 1113, Bulgaria 3 Institute of Astronomy, Bulgarian Academy of Sciences, Sofia 1784, Bulgaria Received 17 Feb 2014, accepted 19 Mar 2014 Published online later Key words astronomical databases: catalogs We present the archive of the wide-field plate observations obtained at the University Observatory Jena, which is stored at the Astrophysical Institute of the Friedrich Schiller University Jena. The archive contains plates taken in the period February 1963 to December 1982 with the 60/90/180-cm Schmidt telescope of the university observatory. A computer- readable version of the plate metadata catalogue (for 1257 plates), the logbooks, as well as the digitized Schmidt plates in low and high resolution are now accessible to the astronomical community.This paper describes the properties of the archive, as well as the processing procedure of all plates in detail. c 2014 WILEY-VCH Verlag GmbH& Co. KGaA, Weinheim 1 Introduction Großschwabhausen,about 10 km to the west of Jena. Archi- tect of the telescope building was Hans Schlag, an architect The large astronomical plate collections provide unique re- who together with J. Schreiter is also famous for the Plan- sources for photometric and astrometric studies of astro- etarium in Jena, built in 1926. -
Catalogue of Excitation Classes P for 750 Galactic Planetary Nebulae
Catalogue of Excitation Classes p for 750 Galactic Planetary Nebulae Name p Name p Name p Name p NeC 40 1 Nee 6072 9 NeC 6881 10 IC 4663 11 NeC 246 12+ Nee 6153 3 NeC 6884 7 IC 4673 10 NeC 650-1 10 Nee 6210 4 NeC 6886 9 IC 4699 9 NeC 1360 12 Nee 6302 10 Nee 6891 4 IC 4732 5 NeC 1501 10 Nee 6309 10 NeC 6894 10 IC 4776 2 NeC 1514 8 NeC 6326 9 Nee 6905 11 IC 4846 3 NeC 1535 8 Nee 6337 11 Nee 7008 11 IC 4997 8 NeC 2022 12 Nee 6369 4 NeC 7009 7 IC 5117 6 NeC 2242 12+ NeC 6439 8 NeC 7026 9 IC 5148-50 6 NeC 2346 9 NeC 6445 10 Nee 7027 11 IC 5217 6 NeC 2371-2 12 Nee 6537 11 Nee 7048 11 Al 1 NeC 2392 10 NeC 6543 5 Nee 7094 12 A2 10 NeC 2438 10 NeC 6563 8 NeC 7139 9 A4 10 NeC 2440 10 NeC 6565 7 NeC 7293 7 A 12 4 NeC 2452 10 NeC 6567 4 Nee 7354 10 A 15 12+ NeC 2610 12 NeC 6572 7 NeC 7662 10 A 20 12+ NeC 2792 11 NeC 6578 2 Ie 289 12 A 21 1 NeC 2818 11 NeC 6620 8 IC 351 10 A 23 4 NeC 2867 9 NeC 6629 5 Ie 418 1 A 24 1 NeC 2899 10 Nee 6644 7 IC 972 10 A 30 12+ NeC 3132 9 NeC 6720 10 IC 1295 10 A 33 11 NeC 3195 9 NeC 6741 9 IC 1297 9 A 35 1 NeC 3211 10 NeC 6751 9 Ie 1454 10 A 36 12+ NeC 3242 9 Nee 6765 10 IC1747 9 A 40 2 NeC 3587 8 NeC 6772 9 IC 2003 10 A 41 1 NeC 3699 9 NeC 6778 9 IC 2149 2 A 43 2 NeC 3918 9 NeC 6781 8 IC 2165 10 A 46 2 NeC 4071 11 NeC 6790 4 IC 2448 9 A 49 4 NeC 4361 12+ NeC 6803 5 IC 2501 3 A 50 10 NeC 5189 10 NeC 6804 12 IC 2553 8 A 51 12 NeC 5307 9 NeC 6807 4 IC 2621 9 A 54 12 NeC 5315 2 NeC 6818 10 Ie 3568 3 A 55 4 NeC 5873 10 NeC 6826 11 Ie 4191 6 A 57 3 NeC 5882 6 NeC 6833 2 Ie 4406 4 A 60 2 NeC 5879 12 NeC 6842 2 IC 4593 6 A -
Planetary Nebula 168 Planetary Nebula 168
Planetary nebula 168 Planetary Nebula 168 Pagina 1 Planetary nebula 168 . o ) . ) . R N ' x e e g c n n m t A i B z z a . a r e i i o Object Other o Class NGC Description U m a m R S S h D C ( M S h ( C 14 NGC 7662 PK 106-17.1 AND 23 25.9 +42 32 8,6 5,6 17 s 14 s 4(3) !!! Planetary or annular neb,vB,pS,R,blue 138 PK 315-13.1 He2-131 APS 15 37.2 -71 55 11,8 6,8 4.9 s 138 PK 308-12.1 He2-105 APS 14 15.5 -74 13 12 12 35 s 66 IC 4846 PK 27-9.1 AQL 19 16.5 -09 03 12 4,5 2 s 2 stellar 66 NGC 6790 PK 37-6.1 AQL 19 23.0 +01 31 11,4 5,9 2 s 2 B,eS,stell=9.5m 66 NGC 6803 PK 46-4.1 AQL 19 31.3 +10 03 11 6,4 4 s 2a stellar 66 NGC 6741 PK 33-2.1 AQL 19 02.6 -00 27 12 7 9 s 7 s 4 Planetary,stellar 42 PK 52- 2.2 Merrill 1-1 AQL 19 39.1 +15 56 11,8 7,7 3 s 4 13''-pF,vS,R,BM at 165X, averted viz helps 66 NGC 6751 PK 29-5.1 AQL 19 05.9 -06 00 12 9,2 20 s 3 pB,S 66 NGC 6804 PK 45-4.1 AQL 19 31.6 +09 14 12,4 11 63 s 50 s 4(2) cB,S,iR,rrr 65 NGC 6852 PK 42-14.1 AQL 20 00.7 +01 44 11.4p 11,2 28 s 4 F neb,am st 66 NGC 6781 PK 41-2.1 AQL 19 18.5 +06 32 11,8 12,8 111 s 109 s 3b(3) F,L,R,vsbM disc 66 NGC 6772 PK 33-6.1 AQL 19 14.6 -02 42 14 99,9 75 s 55 s 3b(2) vF,L,R,vvlBM,r 66 PK 31-10.1 M3-34 AQL 19 27.1 -06 35 12,4 99,9 6.0 s 5.1 s 2 66 PK 37- 3.2 Abell 56 AQL 19 13.1 +02 53 12,4 99,9 188 s 174 s 4 64 NGC 7009 PK 37-34.1 AQR 21 04.2 -11 22 8,3 6,2 28 s 23 s 4(6) !!! vB,S,elliptic 87 NGC 7293 PK 36-57.1 AQR 22 29.6 -20 50 6,3 13,6 960 s 720 s 4(3) !,pF,vL,E or biN 116 IC 4642 PK 334-9.1 ARA 17 11.8 -55 24 12,4 9,6 15 s 4 stellar 115 PK 342-14.1 Shapley 3 ARA 18 07.4 -51 03 11,9 12,4 36 s 116 IC 1266 PK 345-8.1 ARA 17 45.6 -46 05 12,3 99,9 13 s 4 stellar,gaseous spectrum-Pickering 56 PK 173- 5.1 K2-1;SS 38 AUR 05 08.1 +30 48 12 15,5 132 s 3 13''-pF,pL,R,nBM at 165X, 3* invol 32 IC 2149 PK 166+10.1 AUR 05 56.4 +46 06 10 99,9 12 s 6 s 3b(2) S,vB 32 PK 169-0.1 AUR 05 19.2 +38 11 12 99,9 32 s Pagina 2 Planetary nebula 168 . -
A. L. Observing Programs Object Duplications
A. L. OBSERVING PROGRAMS OBJECT DUPLICATIONS Compiled by Bill Warren Note: This report is limited to the following A. L. observing programs: Arp Peculiar Galaxies; Binocular Messier; Caldwell; Deep Sky Binocular; Galaxy Groups & Clusters; Globular Cluster; Herschel 400; Herschel II; Lunar; Messier; Open Cluster; Planetary Nebula; Universe Sampler; and Urban. It does not include the other A. L. observing programs, none of which contain duplicated objects. Like the A. L. itself, I’m using constellation names, not genitives (e.g., Orion, not Orionis) with double stars as an aid for beginners who might be referencing this. -Bill Warren Considerable duplication exists among the various A.L. observing programs. In fact, no less than 228 objects (8 lunar, 14 double stars and 206 deep-sky) appear in more than one program. For example, M42 is on the lists of the Messier, Binocular Messier, Universe Sampler and Urban Program. Duplication is important because, with certain exceptions noted below, if you observe an object once you can use that same observation in other A. L. programs in which that object appears. Of the 110 Messiers, 102 of them are also on the Binocular Messier list (18x50 version). To qualify for a Binocular Messier pin, you need only to find any 70 of them. Of course, they are duplicates only when you observe them in binocs; otherwise, they must be observed separately. Among its 100 targets, the Urban Program contains 41 Messiers, 14 Double Stars and 27 other deep-sky objects that appear on other lists. However, they are duplicates only if they are observed under light-polluted conditions; otherwise, they must be observed separately. -
October's Meeting
October 2008 October’s Meeting Calendar Inside this Issue Sep 4, 2008 – “ Past Saturn and The next meeting of S*T*A*R will be 7 More Years to Pluto: ” New on Thursday, October 2. Our program Horizons Mission, Michael October’s Meeting will be “An Idea That Would Not Die” Lewis, NASA Solar System 1 2008-2009 Calendar by Robert Zimmerman. All are Ambassador welcome. The meeting will begin Oct 2, 2008 – " An Idea That President’s Corner promptly at 8:00pm at the Monmouth Would Not Die" by Robert September Meeting Museum on the campus of Brookdale 2 Zimmerman Minutes Community College. Extreme Starburst Editor’s Corner Nov 6, 2008 – “TBD" 3 Dec 4, 2008 – “Low Energy Thanks to Gavin Warnes, Steve Fedor, Routes to the Moon and & Randy Walton for contributing to this Beyond” by Dr. Edward month’s Spectrogram. Belbruno, Innovative Orbital 4 Design, Inc., Princeton Reminder to pay membership dues S*T*A*R Membership University $25/individual, $35/family. Donations Celestial Events 5 are appreciated. Make payments to Paul Jan 8, 2009 - “Celestial Nadolny at the October meeting or mail Navigation” by Justin Dimmell, In the Eyepiece a check payable to S*T*A*R Island School, Eleuthera, Astronomy Society Inc to: 6 Bahamas S*T*A*R Astronomy Society Moon Phases P.O. Box 863 Feb 5, 2009 - "TBD" 7 Jupiter Moons Calendar Red Bank, NJ 07701 Mar 5, 2009 - “Solar Saturn Moons Calendar Telescopes" by Alan Traino of Astro Crossword Puzzle Lunt Solar Systems November Issue 8 Apr 2, 2009 – “ TBD ” Please send articles and contributions for the next Spectrogram by Friday, May 7, 2009 – “TBD” October 24 . -
Close Binary Stars in the Galactic Open Clusters
Close Binary Stars in the Galactic Open Clusters Kadri Yakut University of Ege, Department of Astronomy and Space Sciences 35100, İzmir-Turkey The IMPACT of BINARIES on STELLAR EVOLUTION July 4, 2017, Garching-Germany (Binary) stellar evolution the equation of the nuclear hydrostatic the radiative opacity state reaction network equilibrium (from core to surface (pressure vs. radiative/convective) gravity) Convection with rotationally driven mixing and diffusive the mixing-length semi-convective separation of abundances (Ap, Am and theory stellar wind mixing Fm stars) mass-loss (dynamo action) convective core tidal friction overshooting (circularize orbits) Evolution Codes Cambridge STARS Code -Eggleton (1971-73) -Pols, Tout, Eggleton, Zhanwen (1995) EV Code -Hurley, Pols, Tout (2000) -Yakut & Eggleton (2005) -Eldridge+ -Eggleton (2006) -Eggleton & Yakut (2017) Close binary stars (CBS) “close binary” • à P is short • à tidal force & RLOF play important roles • à AM, cMT,ncMT, ML, AML and NE • à synchronously rotating • à circular orbit CBS types: -Detached (D) [e.g, RS CVn, Giant+MS, Giant+Giant] -Semi-detached (SD) [e.g. NCB, CV, X-ray binaries, AM CVn, ..] -Contact (C) [e.g., LTCB=W UMa, ETCB] close binary stars (CBS) M, y, z, α, dM/dt + Mt, q, Pbin, dMt/dt, P3, … Single Star: Model of the Sun from its birth to its dead Hypothetical mass-loss and dynamo activity during the Sun's evolution. Today BC 4.525.000.000 Eggleton & Yakut (2017) [MNRAS, 468, 3533] 1-Non-Conservative Evolution of Close/Interacting Binary Stars: Low-mass binary system 1.19 Ms + 0.94 Ms, 0.75 days Yakut & Eggleton (2005, 2018) 2- Non-Conservative Binary Evolution: High-mass binary system V382 Cyg (O6.5 V + O6 V) New observationsà Ege University Observatory Yaşarsoy & Yakut (2013) 8 [AJ, 145, 9] 3-Binary system with giant components: 60 systems Eggleton & Yakut (2017) [MNRAS, 468, 3533] The model of Capella seems to fit the observations very well!!! Primary- Aa Secondary Ab Figure 1.